The neuronal dopamine transporter (DAT) plays a key role in terminating dopaminergic chemical neurotransmission; thus, the study of the regulation of DAT activity is important in defining parameters relevant to the control of dopaminergic neurotransmission. Interpretation of the results from previous work of this laboratory suggests that occupation of presynaptic autoreceptors increases DAT activity. Second messenger signaling related to kinetic upregulation of DAT has not been examined previously. However, others have shown that protein kinase C activity may downregulate DAT activity, whereas protein kinase A has shown variable results. Herein it is shown that protein kinase A activity mediates the kinetic upregulation of DAT. Quinpirole increased DAT activity that was blocked by sulpiride and the protein kinase A selective inhibitor H-89. Brief incubations with forskolin and 8-bromo-cAMP (8-Br-cAMP) were found to stimulate striatal DAT activity by increasing the Vmax of transport without affecting the Km. Exposures >15 min had no effect. The 8-Br-cAMP-stimulated increases in DAT activity were blocked by pre-exposure to H-89. Thus, second messenger signaling via the cAMP cascade may mediate kinetic upregulation of DAT. Kinetic analyses of the results suggest that either insertion of DAT into the membrane or activation of pre-existing DAT within the membrane mediates the regulation.

Aims To refine the Cue Utilization and Engagement in Dementia mealtime video‐coding scheme and examine its ease of use, feasibility, and inter‐rater reliability in assessing the food intake process and dyadic verbal and nonverbal interactions. Design This study was a secondary analysis of 110 videotaped observations of mealtime interactions collected under usual care conditions from a dementia communication trial during 2011–2014. Methods The videos involved 29 staff and 25 residents with dementia (42 unique staff‐resident dyads) in nine nursing homes. Data coding and analysis were performed in 2018–2019. Logs of coding challenges with matched solutions and coding time were collected. Inter‐rater reliability was examined through rating of randomly selected 22 videos across four trained coders. Results It took a mean of 10.81 hr to code a one‐hour video using the refined coding scheme. Coding challenges, including identification of key intake process characteristics and differentiation of similar verbal or nonverbal behaviours, were identified with appropriate solutions. The refined coding scheme had good inter‐rater reliability (Cohen's Kappa range = 0.93 – 0.99, 95% CI = 0.92 – 0.99). Conclusion Findings supported preliminary evidence on feasibility, usability and inter‐rater reliability of the refined coding scheme. Future psychometric testing is needed in diverse populations with dementia across different care settings. Impact Existing tools assessing the food intake process and dyadic interactions are few and have limited feasibility and/or reliability and fail to capture the complexity and dynamics of mealtime care. The refined coding scheme showed preliminary feasibility, usability, and inter‐rater reliability. In consideration of the balance between time intensity and the richness of data obtained, the tool may be appropriate and useful in addressing certain research inquires (e.g., characterizing and clustering dyadic behaviours, temporal relationship between behaviours and intake) pertaining older adults with or without dementia and their formal or informal caregivers.

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Aims To characterize dyadic mealtime verbal interactions and examine the associations with staff and resident characteristics. Design A secondary analysis of 110 videotaped mealtime observations collected from a dementia communication trial during 2011–2014. Methods Videos involved 25 residents with dementia and 29 staff in nine nursing homes. Verbal behaviours (utterances) were coded during 2018–2019 using the Cue Utilization and Engagement in Dementia mealtime video‐coding scheme, addressing eight positive behaviours and four negative behaviours. Bivariate analyses and multivariate regression models were used. Results Staff spoke three times more frequently (76.5%) than residents (23.5%). Nearly all staff utterances were positive (99.2%); 85.1% of residents' utterances were positive and 14.9% negative. Staff positive utterances were correlated with their negative utterances and resident positive and negative utterances. Staff negative utterances were correlated with resident negative utterances. Resident positive and negative utterances were correlated. Resident positive utterances were significantly associated with staff care‐giving length in the current nursing home (OR = 1.430, 95% CI = 1.008, 2.027). Resident negative utterances were significantly associated with resident gender (female versus male, OR = 11.892, 95% CI = 1.237, 114.289) and staff years worked as a caregiver (OR = 0.838, 95% CI = 0.710, 0.989). Staff positive and negative utterances were not associated significantly with any participant characteristics. Conclusions Staff engage residents using primarily positive verbal strategies. Staff–resident mealtime verbal interactions were dynamic, interactive, and complex and related to multiple individual characteristics. Impact Positive dyadic mealtime interactions are critical to engage residents in eating. Little work has characterized dyadic mealtime interactions, limiting the development of effective interventions. Findings showed staff–resident mealtime verbal interactions were primarily positive, inter‐related, and associated with multiple individual characteristics. Findings inform directions to improve mealtime care practice and develop person‐centred mealtime interventions targeting modifiable factors, including staff care‐giving experiences.

Editor's note: This article is by 22 nursing gerontology experts who are all advocates of nursing home reform. They are listed at the end of this article.